Remove the dts/ directory

DTS_ROOT points to platform/ec/zephyr now, so this is unused.

BUG=b:177003034
TEST=CQ

Change-Id: I4b36d8c6e6ebdb252b7debadf3bd4293a3d58f37
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/zephyr-chrome/+/2633884
Commit-Queue: Jack Rosenthal <jrosenth@chromium.org>
Commit-Queue: Simon Glass <sjg@chromium.org>
Tested-by: Jack Rosenthal <jrosenth@chromium.org>
Auto-Submit: Jack Rosenthal <jrosenth@chromium.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
5 files changed